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This list includes some basic information for encoding those variables in netCDF. A more detailed information page about the encoding in netCDF will be found in the Guide to NetCDF encoding for C3S seasonal providers, which should be considered the definitive specification for the data encoding of the files to be provided.
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(1) GRIB data streams could contain those variables as a composite field with parameter ID=139
Daily instantaneous data
GRIB | netCDF | ||||||
time step | name | parameter ID | units | CF standard name | canonical units | ||
24h | Sea-ice cover | 31 | (0-1) | sea_ice_area_fraction | 1 | ||
24h | Volumetric soil water layer 1 (2) | 39 | m3 m-3 | moisture_content_of_soil_layer (2) | kg m-2 | ||
24h | Volumetric soil water layer 2 (2) | 40 | m3 m-3 | ||||
24h | Volumetric soil water layer 3 (2) | 41 | m3 m-3 | ||||
24h | Volumetric soil water layer 4 (2) | 42 | m3 m-3 | ||||
24h | Snow depth | 141 | m of water equivalent | lwe_thickness_of_surface_snow_amount | m | ||
24h | Snow density | 33 | kg m-3 | snow_density | kg m-3 | ||
| 24h | Total column water vapour | (3)137 | kg m-2 | atmosphere_mass_content_of_water_vapor | (3)kg m-2 | ||
| 24h | Total column cloud liquid water (3) | 78 | kg m-2 | atmosphere_mass_content_of_cloud_liquid_water (3) | kg m-2 | ||
| 24h | Total column cloud ice water | (3)79 | kg m-2 | atmosphere_mass_content_of_cloud_ice | (3)kg m-2 | ||
(2) soil water content should be provided for all native model levels (so 39-42 GRIB parameter IDs just apply to ECMWF/IFS soil model)
(3) some details about these total column water quantities is still under discussion, specifically the convenience for time-aggregation (averaging) and some encoding details.
Daily time-aggregated data (accumulations, max/min,etc)
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